Barrel type engine

ABSTRACT

THE DISCLOSED BARREL-TYPE ENGINE INCLUDES A PLURALITY OF PREFERABLY GENERALLY KEYSTONE-SHAPED PISTONS ARRANGED ANNULARLY WITHIN AN ELONGATE HOUSING OF GENERALLY CIRCULAR CROSS SECTION. THE PISTONS ARE ARRANGED FOR PARALLEL LONGITUDINAL RECIPROCATION SIMULTANEOUS WITH THEIR ROTATION WITHIN AND ABOUT THE HOUSING. THIS COMBINATION OF RECIPROCATORY AND ROTARY MOTION IS TRANSLATED TO A LONGITUDINALLY EXTENDING SHAFT THROUGH A CAM COUPLING CIRCUMSCRIBING THE HOUSING AND HAVING LONGITUDINALLY EXTENDING UNDULATIONS. PREFERABLY BOTH ENDS OF THE PISTONS ARE WORKING ENDS.

United States Patent [72] inventor Edward M. Poole 951 Parkway Blvd., Alliance, Ohio 44601 [21] Appl. No. 815,878 [22] Filed Apr. 14, 1969 [45] Patented June 28, 1971 [54] BARREL TYPE ENGINE 10 Claims, 7 Drawing Figs.

[52] US. Cl 123/45, 91/197,92/57, 123/43, 123/51, 123/58 [51] Int. Cl ..F02b 53/00, F0lb 13/00, FOlb 13/04 [50] Field of Search 123/45,43, 58, 51 (B), 52 (B), 43 (A), 43 (C); 92/57; 91/197, 196, 177, 176; 103/121, 162; 230/140; 1/178 [56] References Cited UNITED STATES PATENTS 657,409 9/1900 Gould l23/43X 1,229,009 6/1917 Allison 230/178 1,569,525 1/1926 Owens... 123/43 1,728,514 9/1929 Snyder 92/177X 1,761,123 6/1930 Gruver 92/177X Primary Examiner-Wendell E. Burns AttorneyEdward W. Mentzer PATENTED JUN28 l9?! SHEET 1 OF 3 PATENTED JUN28 19m 35 7 53 SHEET 2 OF 3 FIG.3B FIGLSA FIG. 3 D

PATENTED JUN28 |97| SHEET 3 OF 3 FIG.4

BARREL TYPE ENGINE BACKGROUND OF THE INVENTION This invention relates generally to an engine commonly referred to as a barrel-type having a plurality of pistons arranged in a generally circular pattern and being arranged for parallel longitudinal reciprocation. It is known in the art that such barrel-type engines may be fired at both ends, i.e., both ends of the piston may be working ends operating with suitably provisioned cylinders.

Although barrel-type engines have been constructed heretofore, they have never attained a marked degree of acceptance, primarily because of the mechanical difficulties inherent in translating the reciprocatory motion of the annularly arranged pistons into usable shaft rotation. Furthermore, although, the barrel-type engine provided certain space advantages over more conventional in-line or V-type engines, it provided no greater power output to weight or space ratios; moreover the arrangement of circular pistons and cylinders in an annular pattern created cooling and lubricating problems far greater than those of the more conventional engine.

Accordingly, it is the primary object of the present invention to provide a barrel-type engine wherein the previously encountered problems have been overcome to the extent that the present engine has distinct advantages over the conventional type engines insofar as the normal criteria are concerned, namely; power output to weight or space ratio; mechanical simplicity and minimum imbalance of forces due to movement of the parts.

SUMMARY OF THE INVENTION The engine disclosed herein comprises an elongate housing of generally circular cross section. An axially disposed shaft is rotatably mounted in and extends outwardly from the housing. A plurality of longitudinally extending, generally keystoneshaped pistons are disposed annularly within the housing and are arranged for parallel longitudinal and sequential reciprocation. Each of the pistons has at least one working end, and preferably has a pair of working ends at the longitudinal extremities of the engine. The pistons, in addition to reciprocating within said housing, simultaneously rotate within and about the housing. Means are provided interconnecting the shaft and pistons to translate motion therebetween and to effect the combination reciprocatory and rotary piston motion. This combination of rotation and reciprocation effects an efficient utilization of the engine displacement volume not heretofore realized. The end of the housing is enclosed so as to form an annular cylinder chamber between the piston working ends and the housing end cover. Exhaust and intake port means are provided in the end cover to afford communication with the cylinder chamber. The annular cylinder chamber is divided into a plurality of generally keystone-shaped chambers (in-each of which one of the pistons is operable) by a plurality of radially disposed abutments which rotate with the pistons. The abutments have their ends in close spaced, substantially sealing relationship with the end cover so as to form effective seals between annularly adjacent rotating piston chambers.

The engine is preferably intended for use as an internal combustion engine, in which event a fuel/air mixture is supplied to the cylinder chamber, an ignition system is included, and exhaust means are provided. Alternatively the engine can be used to generate power by supplying an expandable gas to the cylinders. Alternatively by powering the engine via the shaft, the engine can be used as a compressor.

BRIEF DESCRIPTION OF THE DRAWINGS The engine disclosed herein, in the form of an internal combustion engine, is depicted in the following several views which should be collectively considered for a proper understanding of the invention.

FIG. 1 is a longitudinal sectional view of the engine disclosed herein, saidsectional view being taken substantially along line 1-1 of FIG. 3.

FIG. 2 is a partial cross-sectional view taken along line 2-2 of FIG. 1.

FIG. 3 consists of sectional quadrants labeled FIG. 3A, 3B, 3C and 3D, each of which is a partial cross-sectional view taken.respectively along lines 3A-3A, 38-38, 3C-3C, and 3D-3D of FIG. 1.

FIG. 4 is a cross-sectional view taken along line 44 of FIG. 1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to the various FIGS., and particularly to FIG. 1, the engine includes a generally cylindrical housing comprising portions 10 and 12 connected together at and by the bolted flange 14. Each portion has an end cover 16 having therein a central opening, inwardly of which extends a tubular inner housing 18. A shaft 20 extends through one of the inner housings 18 (right end of FIG. 1), the shaft 20 being supported at its out board end by a low friction sleeve bearing 22. Just beyond the innermost end of the right-hand inner housing 18, the shaft 20 is supported in a coupling 19 and is formed with an outwardly extending flange portion 21A, the portion 21A and the coupling 19 being bolted to lugs 23A which connect with engine abutments 40, a further description of which will follow. A stub shaft 25 extends inwardly through the other (left-hand) inner housing 18. The stub shaft 25 being splined at its innermost end. The splined end is engaged with a splined coupling 27 which is bolted to lugs 238 (which connect with engine abutments 40) and to a flange portion 218 of the shaft 20, the end of which is adjacent to and coaxial with the splined end of stub shaft 25. Stub shaft 25 is supported and positioned at its outboard end by radial and thrust bearing assembly 29.

From the above description, it should be readily apparent that the interconnected shafts 20 and 25, together with attachments, form a substantially unitary, relatively simple and straight shaft assembly extending all the way through the housing and being adequately supported therein, and having facility for accommodating end-play. Also noteworthy is the fact that the abutments 40 are rigidly connected with the shaft assembly, so that rotation of the abutments 40 within the housing necessarily causes rotation of the shafts 20 and 25.

With more specific reference to FIGS. 2 and 3, each end of the housing is formed with an annular cylinder chamber 32 bounded by inner cylinder wall 34 and outer cylinder wall 36, which walls are concentric with and cooperate with housing portions 10 and 12 and with inner housings 18 and cylinder end walls 16A to form coolant flow chambers 38. Within each annular cylinder chamber 32.there is a plurality of annularly spaced, generally keystone-shaped pistons 30 between which are disposed engine abutments 40 of similar general cross-sectional shape at their ends, but of smaller width. The abutments 40 extend substantially from one end cover 16 to the other, while the pistons 30 are shorter by a distance substantially equal to the length of their stroke. Both the pistons 30 and the abutments 40 are formed with suitable structural portions to withstand the forces exerted thereon, and with suitable ingress and egress means for lubricant and/or coolant; moreover, the working ends of the pistons 30 and abutments 40 are hollow to allow the confinement therein of a coolant as is known in the art.

The inner and outer cylinder walls 34 and 36 are formed with suitable grooves 42 arranged to confine compression and lubricant control rings of the types normally utilized to wipe and seal the pistons relative to the cylinder walls in conventional internal combustion engines. Each abutment 40 is fitted with a U-shaped seal 45, the central portion of which is radially disposed with respect to the axis of the engine. The legs of the U-shaped seals 45 extend along the inner and outer walls of the abutments 40 thereby effecting a seal with the inner and outer cylinder walls 34 and 36. The central portion of the U- shaped seals 45 are in running contact with the cylinder end walls 16A, so as to effectively divide each annular cylinder chamber 32 into a plurality of keystone-shaped chambers, in

each of which a working end of a cylinder 30 is operative. To provide for a seal between the radial walls of each abutment 40 and its adjacent cylinders 30, each abutment 40 is fitted with a pair of L-shaped seals 46, each of which has its longer leg between the abutment 40 and the piston 30 and has its shorter leg along the inner side of the abutment 40.

From the above, it should be recognized that each working end of each cylinder 30 is operative within an isolated generally keystone-shaped cylinder chamber sealed at its boundaries by U-shaped seals 45, L-shaped seals 46 and inner and outer rings 42. It should be kept in mind that each such individual cylinder chamber is rotating within and about the annular chamber 32 during operation of the engine.

The synchronization of the pistons 30 with respect to theiraxial travel is accomplished through a cam assembly the principal portion of which is a pair of parallel, spaced, inwardly projecting cam runners 50 that extend about the housing and are shaped with undulations to control the axial movement of the pistons 30 in the desired manner. The undulations are shaped to produce the desired acceleration cycle of the pistons, e.g., simple harmonic motion or uniform acceleration. The cam runners 50 are retained by an outwardly extending flange portion 49 which is affixed to the flange 14. Each piston 30 has centrally connected thereto (as by threaded connectors 51) a pair of needle or ball bearing mounted cam follower wheels 52 that engage the inner faces of the cam runners 50. A plate 54 is used to stiffen each pair of follower wheels 51 against inertia forces at each end of each stroke of the pistons 30.

In recognition of relatively large mass of the rotating parts (pistons 30 and abutments 40) and the fact that centrifugal force increases as a square function of the speed, to reduce the wear on and to restrain the rotating parts, a floating ring assembly 60 is provided at each end of the engine between the central cam assembly and the working ends. Each floating ring assembly 60 includes a ring 62 having affixed to its inner surface a plurality of hardened, flat plates 64, one such plate 64 being adjacent each piston 30. Between each plate 64 and its adjacent piston 30, there is provided a pair of cylindrical rollers 66 suitably confined in a cage 67 and arranged to allow free longitudinal movement of each piston 30 while the pistons 30 rotate within the annular chamber 32. The axial movement (relative to the engine axis) of the rollers 66 will be one-half the axial travel of the pistons 30; however the ring 62 will remain axially stationary because it is subject to balanced forces from the several pistons 30.

Referring now specifically to FIG. 4, the cylinder end wall 16A is formed with port means for purposes of allowing ingress and egress of the engine working fluids. Each set of ports 70 includes a pair of inlet ports 71A and 71B, and three exhaust ports 72A, 72B and 72C, the specific functions and relationships of which will be discussed hereinafter. Note on the left-hand side of FIG. 1, that the ports pass completely through the end cover 16 and end wall 16A. To exemplify the operation of the port system, note that as the pistons 30 and abutments 40 rotate, the parts 72A, 71A and 71B will sequentially be in communication with the keystone-shaped portion of the cylinder chamber 32 identified with a single piston 30. In other words as one of the U-shaped seals passes over the leading edge of the exhaust port 728, the port 72B will be opened to the keystone-shaped portion of the cylinder chamber 32 serving the piston 30 having that particular U- shaped seal 45 at its leading side. Each set of ports 70, is connected with suitable manifolds (not shown) through which the preferably served by separate manifold systems.

A pair of openings 74 are provided in each end wall 16 for insertion ofa glow plug or other suitable ignition means.

Lubrication of the floatingring assemblies 60, the cam runners 50 and the cam follower wheels 52 is accomplished by oil supplied to spray nozzles 76 spaced about the periphery of the engine. The pistons 30 and abutments 40 are cooled by forcing oil in through grooves 43 in a conventional manner. The oil is collected in a sump pan 78 from which it may be cooled, filtered andrecirculated in a conventional manner.

The particular embodiment of the invention shown in the drawings is an internal combustion engine; however, the invention is not intended to be so limited. The present invention (with suitable accessories and appurtenances and adaptations of the valve system) is adaptable for use also as an external combustion engine, a steam engine, a fluid compressor, a hot gas producer for a gas turbine plant, or a fluid expander.

The accessories for use in conjunction with depicted internal combustion engine may be of a conventional type. Noteworthy is the fact that shaft 20 could be utilized to power the accessories, leaving shaft 25 as the main power output shaft.

The invention embodiment shown is an 8-cylinder, twostroke cycle, double-ended engine, i.e., each working end of each piston is subjected to one application of power per each complete cycle. This particular arrangement dictates that the cam runners 50, have a pair of complete lobes so as to produce two firing cycles per piston end per revolution. This particular feature results in balanced thermal and mechanical conditions at each end of the engine. Furthermore, an axially mechanically balanced condition obtains because the pistons 30 at one end of the engine always have an equal number of counterpart pistons 30 at the other end in exactly the same position in the firing cycle; i.e., the momentum of the pistons 30 moving toward one end equals the momentum of the pistons 30 moving toward the other end. The double-ended piston feature also enhances the engine from the standpoint of horsepower/weight ratio.

For purposes of further description and with particular reference to FIG. 4, assume that a piston 30 is in the position indicated by the radial lines a-a, and that in that position the glow plug has ignited a fuel/air mixture in that segment of the cylinder chamber 32. The force of explosion of the fuel exerts an axial force on the piston 30 which causes rotation of the piston because of its connection to the cam runners 50. When the piston 30 has rotated to the position shown by the lines b-b, the residual pressure on the piston 30 is vented through exhaust ports 72A and 728. Further rotation closes exhaust port 72A and opens inlet port 71A (while exhaust port 728 is still open), thus commencing what is referred to as a scavenging operation wherein the incoming air force the exhaust gases out. This scavenging operation continues by interaction of inlet ports 71A and 71B and exhaust ports 72B and 72C until the piston reaches the position shown by lines c-c, at which time only the inlet port 718 is open to charge the cylinder space with air. Also at this time the fuel is injected into the cylinder space. For reference purposes note that in moving from position a-a to position c-c the piston 30 has rotated slightly over and has made a complete axial stroke (and is now being subjected to firing at its other working end). The rotation from position 0-0 to position d-d is coincident with axial movement of the piston 30 resulting in compression of the fuel air mixture. At position d-d, the opposite glow plug fires, and the above described sequence is repeated. The rotation from position a-a to position d-d represents one complete firing cycle. This same sequence of operations takes place with respect to each of the pistons 30 at each end of the engine, opposite ends of the engine being oriented at 90 of rotation with respect to each other to obtain the necessary firing sequence.

1 claim:

I. An engine comprising an elongate housing of general circular cross section, a shaft rotatably mounted in and extending outwardly from said housing, a plurality of longitudinally extending pistons of generally keystone-shaped cross section arranged annularly within said housing and arranged for parallel longitudinal reciprocation, each of said pistons having a working end, said pistons being rotatable within and about said housing, means interconnecting said shaft and pistons for effecting simultaneous longitudinal reciprocation of said pistons and rotation of said pistons within and about said housing and for translating motion between said pistons and said shaft, means enclosing an annular cylinder chamber adjacent the piston working ends, and means for dividing said annular cylinder chamber into a plurality of generally keystone-shaped chambers, in each of which one of said pistons is operable.

2. An engine according to claim I wherein said means enclosing an annular cylinder chamber includes an end cover which comprises a portion of said housing and said housing has formed therein exhaust port means and intake port means communicating with said annular cylinder chamber, at least one of said port means being formed in said end cover.

3. An engine according to claim 2 wherein said shaft extends longitudinally and axially of said housing, and said means for dividing said chamber includes a plurality of abutments mounted for rotation with said shaft and said pistons, said abutments having their ends in close-spaced relationship with the inner surface of said end cover to effect a substantial seal therebetween.

4. An engine according to claim 3 wherein said annular cylinder chamber is delimited by an inner chamber wall of cir cular cross section concentric with said housing, and said shaft extends through said inner chamber wall longitudinally beyond said end cover.

5. An engine according to claim 3 wherein said pistons are double-acting, each being formed with oppositely disposed working ends, both ends of said housing are enclosed by ported end covers thereby forming a pair of annular cylinder chambers, and said abutments extend into and divide each of said cylindrical chambers into a plurality of generally keystone-shaped chambers.

6. An engine according to claim 1 wherein a cam coupling interconnects said pistons and said housing, said cam coupling having a closed element extending annularly of said housing, and having at least one undulation projecting in a longitudinal direction relative to said housing.

7. An engine according to claim 5 wherein there is provided an even number of said double-acting uniformly spaced pistons, and said closed cam element is formed with a plurality of uniform longitudinally extending undulations arranged so that the pistons at one end of the engine always have an equal number of counterpart pistons at the other end in the same relative position.

8. An engine according to claim 7 said engine being an internal combustion engine, and further comprising means including said intake port means for introducing a combustible substance into said chambers, means for igniting said fuel, and means including said exhaust port means for withdrawing products of combustion from said chambers.

9. An engine according to claim 1 further including a ring within said housing circumscribing and constraining said pistons against radial movement, and bearing means interconnecting said ring and sald pistons, said bearing means being arranged to allow longitudinal reciprocation of said pistons relative to said ring, said ring being rotatable with said pistons.

10. An engine according to claim 3 wherein said cylinders have substantially radial sidewalls relative to the axis of the engine, and wherein the abutments occupy only a minor portion of said annular cylinder chamber. 

